diff --git a/tests/verilog/constparser_f.ys b/tests/verilog/constparser_f.ys
new file mode 100644
index 000000000..3dd3f1323
--- /dev/null
+++ b/tests/verilog/constparser_f.ys
@@ -0,0 +1,6 @@
+read_verilog <<EOT
+module test (y);
+    output signed [2:0] y = 1'b1;
+endmodule
+EOT
+dump
diff --git a/tests/verilog/constparser_f_file.sv b/tests/verilog/constparser_f_file.sv
new file mode 100644
index 000000000..9699a3a2a
--- /dev/null
+++ b/tests/verilog/constparser_f_file.sv
@@ -0,0 +1,3 @@
+module test (y);
+    output signed [2:0] y = 1'bf;
+endmodule
diff --git a/tests/verilog/constparser_f_file.ys b/tests/verilog/constparser_f_file.ys
new file mode 100644
index 000000000..9063cfbf5
--- /dev/null
+++ b/tests/verilog/constparser_f_file.ys
@@ -0,0 +1,2 @@
+logger -expect prefix-error "./constparser_f_file.sv:2: ERROR: Digit larger than 1 used in in base-2 constant." 1
+read_verilog -sv ./constparser_f_file.sv
diff --git a/tests/verilog/constparser_g.ys b/tests/verilog/constparser_g.ys
new file mode 100644
index 000000000..37e31ba20
--- /dev/null
+++ b/tests/verilog/constparser_g.ys
@@ -0,0 +1,6 @@
+logger -expect prefix-error "<<EOT:2: ERROR: syntax error, unexpected invalid token, expecting TOK_BASED_CONSTVAL" 1
+read_verilog <<EOT
+module test (y);
+    output signed [2:0] y = 1'bg;
+endmodule
+EOT